Follow up: @sibi took her to the vet the following day and they administered the usual charcoal treatment. Now it's just a wait and see type of thing for the next week or so. So far she's doing well, and has been eating and acting normally.
The part of the plant she ate was older growth leaves, which are supposed to be less toxic than the tender new growth leaves. I've also heard that the nuts / seeds are the most toxic part of the plant.
Naturally, we're hoping for the best outcome, and we'll be sure to keep this little tort far away from Sagos from now on.
Although the area she was in at the time contains Sagos, it's not part of the area where we normally keep her. So the removal of the plant is not an issue. Believe me when I say that she'll never be around Sagos again!
Follow up: Baby Runt is doing fine after her charcoal treatment, with no signs of any ill effects from her Sago munching misadventure. In fact, she's had a great appetite of late, and has been knocking down the door to her house, demanding to be fed first. So, I guess there's just no stopping the "sulcata mafia".